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1.
Virus Evol ; 8(1): veac030, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35450165

RESUMO

GII.2[P16] and GII.4 Sydney [P16] are currently the two predominant norovirus genotypes. This study sought to clarify their evolutionary patterns by analyzing the major capsid VP1 and RNA-dependent RNA polymerase (RdRp) genes. Sequence diversities were analyzed at both nucleotide and amino acid levels. Selective pressures were evaluated with the Hyphy package in different models. Phylogenetic trees were constructed by the maximum likelihood method from full VP1 sequences, and evolutionary rates were estimated by the Bayesian Markov Chain Monte Carlo approach. The results showed that (1) several groups of tightly linked mutations between the RdRp and VP1 genes were detected in the GII.2[P16] and GII.4[P16] noroviruses, and most of these mutations were synonymous, which may lead to a better viral fitness to the host; (2) although the pattern of having new GII.4 variants every 2-4 years has been broken, both the pre- and the post-2015 Sydney VP1 had comparable evolutionary rates to previously epidemic GII.4 variants, and half of the major antigenic sites on GII.4 Sydney had residue substitutions and several caused obvious changes in the carbohydrate-binding surface that may potentially alter the property of the virus; and (3) GII.4 Sydney variants during 2018-21 showed geographical specificity in East Asia, South Asia, and North America; the antigenic sites of GII.2 are strictly conserved, but the GII.2 VP1 chronologically evolved into nine different sublineages over time, with sublineage IX being the most prevalent one since 2018. This study suggested that both VP1 and RdRp of the GII.2[P16] and GII.4 Sydney [P16] noroviruses exhibited different evolutionary directions. GII.4[P16] is likely to generate potential novel epidemic variants by accumulating mutations in the P2 domain, similar to previously epidemic GII.4 variants, while GII.2[P16] has conserved predicted antigenicity and may evolve by changing the properties of nonstructural proteins, such as polymerase replicational fidelity and efficiency. This study expands the understanding of the evolutionary dynamics of GII.2[P16] and GII.4[P16] noroviruses and may predict the emergence of new variants.

2.
Chemistry ; 16(6): 1903-10, 2010 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-20029916

RESUMO

Hybrid materials doped with novel europium complexes were synthesized using PMMA-co-Sn(12)Clusters (copolymers from oxohydroxo-organotin dimethacrylate and methylmethacrylate) as the matrix material. Two types of hybrid materials were obtained: the physically doped product, PMMA-co-Sn(12)Cluster/Eu(TTA)(3)phen, and the grafted product, PMMA-co-Sn(12)Cluster-co-[EuAA(TTA)(2)phen] (TTA = 2-thenoyltrifluoroacetone, phen = phenanthroline and AA = acrylic acid). The hybrid materials exhibited characteristic luminescence of the Eu(3+) ions, and also showed relative especial optical properties compared with samples just using PMMA as the matrix material. The PMMA-co-Sn(12)Cluster matrix exhibited a high physical doping quantity of [Eu(TTA)(3)phen], which can be attributed to the special structure of this kind of hybrid material. GPC (gel-permeation chromatography), TGA (thermogravimetric analysis), SEM, (1)H NMR, ICP (inductively coupled plasma), (119)Sn NMR, FTIR, and diffuse reflectance techniques were employed to characterize the structures and properties of these hybrid materials.

3.
Chem Commun (Camb) ; (40): 4918-20, 2008 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-18931738

RESUMO

Novel channel structures based on [M(bpdo)(3)](2+) and p-sulfonatocalix[4]arene nanocapsules have been established; these are sustained exclusively by charge-assisted pi...pi interactions and sorption experiments show the porous materials have selective guest sorption properties.

4.
Spine (Phila Pa 1976) ; 43(3): E185-E192, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28591076

RESUMO

STUDY DESIGN: A prospective study. OBJECTIVE: The aim of this study was to evaluate the outcomes and efficacy of using a 10Fr elastic tube with a regular negative pressure ball to treat the operative pleural tear in the complicated single-stage posterior approach thoracic spine surgeries. SUMMARY OF BACKGROUND DATA: In some complicated single-stage posterior approach thoracic spine surgeries, such as total en bloc spondylectomy, pleural tear is quite inevitable. Traditional chest tube with a water-sealed bottle has many shortcomings, as pain, inconvenience, and other complications. In many thoracic surgeries, a smaller-caliber elastic tube has been used to avoid such complications and achieve quick recovery. However, there are concerns about the efficacy and safety of the smaller-caliber elastic tube. METHODS: A prospective trial was performed in 72 patients between April 2008 and March 2012. Pleural tear occurred in 19 patients, among whom 10 patients were inserted a 10Fr elastic tube with a regular negative pressure ball (Group I), and nine were inserted a 28Fr chest tube with a water-sealed bottle (Group II). Comparative evaluation of the clinical and radiographic data was carried out. RESULTS: The basic condition of two groups did not differ significantly. The oxygen saturation monitor, hospital length of stay, average volume, and failure rate of drainage between two groups were not statistically significant. The difference of the visual analog score was significant (1.10 ±â€Š0.35 vs. 3.89 ±â€Š0.59, P < 0.001). CONCLUSION: Patients who received a 10Fr elastic tube with a regular negative pressure ball experienced less pain and a tendency of quicker recovery than those who received a 28Fr chest tube with a water-sealed bottle. The complication rate in Group I was not higher than Group II, indicating an equally good drainage efficacy. LEVEL OF EVIDENCE: 2.


Assuntos
Tubos Torácicos , Drenagem/instrumentação , Complicações Intraoperatórias/cirurgia , Pleura/lesões , Vértebras Torácicas/cirurgia , Adulto , Idoso , Drenagem/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
5.
J Phys Chem B ; 109(13): 6174-82, 2005 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-16851683

RESUMO

The crystal structures of ternary Ln(DBM)(3)phen complexes (DBM = dibenzoylmethane, phen = 1,10-phenanthroline, and Ln = Nd, Yb) and their in situ syntheses via the sol-gel process are reported. The properties of the Ln(DBM)(3)phen complexes and their corresponding Ln(3+)/DBM/phen-co-doped luminescent hybrid gels obtained via an in situ method (Ln-D-P gel) have been studied. The results reveal that the lanthanide complexes are successfully in situ synthesized in the corresponding Ln-D-P gels. Both Ln(DBM)(3)phen complexes and Ln-D-P gels display sensitized near-infrared (NIR) luminescence upon excitation at the maximum absorption of the ligands, which contributes to the efficient energy transfer from the ligands to the Ln(3+) ions (Ln = Nd, Yb), an antenna effect. The radiative properties of the Nd(3+) ion in a Nd-D-P gel are discussed using Judd-Ofelt analysis, which indicates that the (4)F(3/2) --> (4)I(11/2) transition of the Nd(3+) ion in the Nd-D-P gel can be considered as a possible laser transition.

6.
Spine J ; 15(5): 1050-9, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25637466

RESUMO

BACKGROUND CONTEXT: Microcirculatory dysfunction of the sub-endplate is considered to reduce nutrient supply to the intervertebral disc (IVD); however, direct interruption or destruction of blood vessels in the bone marrow of the vertebrae body adjacent to the endplate has not yet been described, especially with regard to the calcification and ossification of the cartilaginous endplate occurring during IVD degeneration. PURPOSE: The purpose of the study was to evaluate the causal relationship between IVD degeneration and blocking of the main blood supply gateway through the endplate. STUDY DESIGN/SETTING: The study describes a new IVD degeneration model induced by ischemic sub-endplate. PATIENT SAMPLE: A total of 40 Sprague-Dawley rats were included in the study group. OUTCOME MEASURES: To assess disc height, a radiograph was taken each month for 4 months. Changes in endplate, nucleus pulposus (NP), and annulus fibrosus (AF) were evaluated by histochemical and immunohistochemical staining to detect IVD degeneration. METHODS: Injection of 30 µL absolute ethanol into the IVD of rat tail at Co7/Co8 was used to induce injury. Controls were injected with 30 µL of phosphate-buffered saline into the IVD at Co8/Co9. RESULTS: In the ethanol-injected group, disc height gradually decreased and bone sclerosis developed in the endplate. In the NP, cell transformation occurred, changing from predominantly vacuolar cells to chondrogenic cells and eventually fibrocartilaginous cells, along with fibrosis of the NP. As degeneration progressed, the AF developed disordered morphology and rough lamellae, and eventually ruptures and fibrosis. The extent of degeneration increased gradually over time, while the wavy tidemark of the growth plate regressed, and eventually disappeared. Initially positive collagen type II staining gradually decreased on the ischemic side of the sub-endplate. Except at the 3-month time point, expression of collagen type II, aggrecan, and Sox-9 in NP decreased gradually as degeneration progressed, compared with the control group. CONCLUSIONS: This model successfully reproduced IVD degeneration, which could be used for etiological studies on IVD degeneration and investigation of nutrient supply disturbance, and may provide a theoretical foundation for clinical intervention and therapy for IVD degeneration in the future.


Assuntos
Degeneração do Disco Intervertebral/etiologia , Disco Intervertebral/irrigação sanguínea , Isquemia/complicações , Cauda/irrigação sanguínea , Animais , Modelos Animais de Doenças , Humanos , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley
9.
Inorg Chem ; 42(23): 7531-4, 2003 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-14606848

RESUMO

A novel coordination polymer [[Cu(L(1))(L(2))(H(2)O)].5H(2)O](n) (1), where L(1) =1,1'-(1,4-butanediyl)bis(imidazole) and L(2) = m-phthalate anion, has been obtained by using an unusual crystallization process. It crystallizes in the orthorhombic space group Pna2(1), which belongs to the crystal class mm2, with a = 9.0521(18), b = 15.401(3), and c = 17.141(3) A, alpha = beta = gamma = 90 degrees, V = 2389.7(8) A(3), and Z = 4. The complex 1 composing a porous supramolecular architecture displays unprecedented four-connected topology of an 8(6) net in coordination polymer chemistry. Thermal gravimetric analysis (TGA) and X-ray powder diffraction (XRPD) patterns for 1 are discussed in detail.

10.
Chemistry ; 10(15): 3761-8, 2004 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-15281160

RESUMO

Hydrolysis of dibenzyltin dichloride in ethanol has been found to give an unprecedented carbonate anion (CO(3) (2-))-bridged double-ladder organooxotin cluster, [(R(2)SnO)(3)(R(2)SnOH)(2)(CO(3))](2) (1, R = C(6)H(5)CH(2)), with five tin atoms in each ladder. With the aim of obtaining organooxotin clusters with large cavities suitable for host-guest chemistry, we used 1,1'-ferrocenedicarboxylic acid (H(2)L(a)) and hexanedioic acid (H(2)L(b)) to replace the carbonate anions (CO(3) (2-)), and thereby clusters [(R(2)SnO)(3)(R(2)SnOH)(2)L(a)](2) (2) and [(R(2)SnO)(3)(R(2)SnOH)(2)L(b)](2) (3) were obtained. When 1 was treated with benzoic acid (HL(c)) in different stoichiometric ratios (1:4, 1:10), ladder cluster (R(2)SnO)(3)(R(2)SnOH)(2)(L(c))(2) (4) and drum cluster [RSn(O)L(c)](6) (5) were obtained. Through the hydrolysis of Cy(2)SnCl(2) (Cy = C(6)H(11)) and (C(6)H(5)CH(2))(2)SnCl(2), two interesting ethanolate-modified clusters [Cy(2)(C(2)H(5)O)SnOSn(C(2)H(5)O)Cy(2)](2) (6) and [(R(2)SnO)(3)(R(2)SnOH)(R(2)SnOC(2)H(5))(CO(3))](2) (7) were obtained. All the tin atoms in these ladder clusters are five-coordinate surrounded by two alkyl groups and three O atoms, and have distorted trigonal-bipyramidal coordination environments with two carbon atoms and one O atom in the equatorial positions and two O atoms in the axial positions. The structures of all these compounds have been established by single-crystal X-ray diffraction analyses.

11.
Acta Crystallogr C ; 58(Pt 12): m613-4, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12466615

RESUMO

In the crystal structure of the title compound, (NH(4))[AsO(2)(OH)(C(6)H(4)NO(2))], the 4-nitrophenylarsonate anions and ammonium cations are linked through hydrogen bonds to form infinite chains along the b axis. The hydroxyl O atom of the 4-nitrophenylarsonate anion acts as both an acceptor and a donor of hydrogen bonds. All atoms are located in general positions.

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